Junkyard Dog
Well-Known Member
Back when my cars of choice were classic Pontiacs one of the biggest ways to pick up horsepower was 3" exhaust, x crossover, and, while these engines were a lot bigger (472-540 or so ci) they were not pushing 8000 rpm, either. Lots of guys, sick of the 3" noise, necked down to 2.5 mufflers. The exhaust gases do not need 3" the entire way to the back, due to cooling (lol, no, its not cold at the mufflers, ever touch one - don't ask me how I know this3" is a waste IMO if you're going to just put a 2.5" on the end of it, but again there's only one way to see the actual numbers. and guys are making big power through the factory 2.5" mufflers
Getting rid of that 2-1/4" section has to be a good size gain but again...
Where are the Engine Masters guys when you need them!?
) but the exhaust cools a lot from intensely hot to just hot (Google says "hundreds of degrees"), and takes up less volume, and therefore does not benefit from 3" at the rear bumper even if it does up near the header.Some of them (Pontiac) ran 3.5" into the x crossover and 3" after.
Maybe the Mustang would not pick up, I dunno, but I bet it would with headers, especially with tuning and an 8,000 rpm redline.
And, yeah, I agree with you about getting rid of the 2.25" restriction has to make some difference by itself.
Maybe I'll pester Q6543 about whether he had a before/after result on just that resonator - he might be sick of me asking about his exhaust at this point.
Sponsored